The following paragraphs are not an admission that anything discussed in them is prior art or part of the knowledge of persons skilled in the art.
International Publication No. WO/2000/001607 discloses a moving handrail construction, for escalators, moving walkways and other transportation apparatus with a handrail having a generally C-shaped cross section and defining an internal generally T-shaped slot. The handrail is formed by extrusion and comprises a first layer of thermoplastic material extending around the T-shaped slot. A second layer of thermoplastic material extends around the outside of the first layer and defines the exterior profile of the handrail. A slider layer lines the T-shaped slot and is bonded to the first layer. A stretch inhibitor extends within the first layer. The first layer is formed from a harder thermoplastic than the second layer, and this has been found to give improved properties to the lip and improved drive characteristics on linear drives.
International Publication No. WO/2009/033270 discloses a method and apparatus for extrusion of an article. A die assembly can apply flows of thermoplastic material to an array of reinforcing cables to form a composite extrusion. A slider fabric can be bonded to one side of the composite extrusion. After exiting the die assembly, the slider fabric can act to support the extrudate as it passes along an elongate mandrel, which can cause the base of the slider fabric to change shape from a flat profile to the final internal profile of the article. The extruded article can then be cooled to solidify the material. The die can include cooling for the slider fabric and means for promoting penetration of the thermoplastic into reinforcing cables.
International Publication No. WO/2009/033272 discloses modified handrails for use in escalators, moving walkways and other transportation apparatus. Handrail can include a configuration for a cable array as a stretch inhibitor that reduces cable buckling under severe flexing conditions. Handrail can also include a configuration for first and second thermoplastic layers in the lip portions that reduces strain and bending stresses and increases fatigue failure life under cyclic loading conditions. Handrail can also include, for the stretch inhibitor, the use of cables comprising large outer strands and small inner strands that enable penetration and adhesion within the first layer and can reduce incidence of fretting or corrosion.
International Publication No. WO/2009/033273 discloses a method and apparatus for pretreatment of slider layer for extruded handrails having a slider layer source, a means of conveying the slider layer to a heating module which subjects the slider layer to an elevated temperature for a residence time, and a means of conveying the slider layer to an extrusion die head. One or more control feeders may be implemented for maintaining portions of the slider layer in a substantially tension-free loop as the slider layer is conveyed from the slider layer source to the extrusion die head. A cooling zone may be included to ensure adequate cooling between the heating module and the extrusion die head. Means for reducing heat transfer between the extrusion die head and the slider layer is also provided.
The entire contents of International Publication Nos. WO/2000/001607, WO/2009/033270, WO/2009/033272 and WO/2009/033273 are hereby incorporated herein by reference.